# Problem 8
# =========
# Find the greatest product of five consecutive digits
# in the 1000-digit number.
#
#     73167176531330624919225119674426574742355349194934
#     96983520312774506326239578318016984801869478851843
#     85861560789112949495459501737958331952853208805511
#     12540698747158523863050715693290963295227443043557
#     66896648950445244523161731856403098711121722383113
#     62229893423380308135336276614282806444486645238749
#     30358907296290491560440772390713810515859307960866
#     70172427121883998797908792274921901699720888093776
#     65727333001053367881220235421809751254540594752243
#     52584907711670556013604839586446706324415722155397
#     53697817977846174064955149290862569321978468622482
#     83972241375657056057490261407972968652414535100474
#     82166370484403199890008895243450658541227588666881
#     16427171479924442928230863465674813919123162824586
#     17866458359124566529476545682848912883142607690042
#     24219022671055626321111109370544217506941658960408
#     07198403850962455444362981230987879927244284909188
#     84580156166097919133875499200524063689912560717606
#     05886116467109405077541002256983155200055935729725
#     71636269561882670428252483600823257530420752963450
#

"""
    Generator that returns consecutive sz-digit
    slices from s_int string, in order, 
    but as an array of ints.
"""
def chunk(s_int, sz):
    start = 0
    stop  = sz
    if len(s_int) < sz:
       yield [int(l) for l in s_int] 
    else:
        while stop <= len(s_int):
            yield [int(l) for l in s_int[start:stop]]
            start += 1
            stop  += 1 

mult = lambda x,y:x*y

lines = [
    "73167176531330624919225119674426574742355349194934",
    "96983520312774506326239578318016984801869478851843",
    "85861560789112949495459501737958331952853208805511",
    "12540698747158523863050715693290963295227443043557",
    "66896648950445244523161731856403098711121722383113",
    "62229893423380308135336276614282806444486645238749",
    "30358907296290491560440772390713810515859307960866",
    "70172427121883998797908792274921901699720888093776",
    "65727333001053367881220235421809751254540594752243",
    "52584907711670556013604839586446706324415722155397",
    "53697817977846174064955149290862569321978468622482",
    "83972241375657056057490261407972968652414535100474",
    "82166370484403199890008895243450658541227588666881",
    "16427171479924442928230863465674813919123162824586",
    "17866458359124566529476545682848912883142607690042",
    "24219022671055626321111109370544217506941658960408",
    "07198403850962455444362981230987879927244284909188",
    "84580156166097919133875499200524063689912560717606",
    "05886116467109405077541002256983155200055935729725",
    "71636269561882670428252483600823257530420752963450"
]

s_int = "".join(lines)

answer = 0
f = chunk(s_int, 5)
for n in xrange(0,len(s_int)-5+1):
    x = reduce(mult, f.next())
    if x > answer:
        answer = x

print "-> ", answer
